Change the list-head structure for in-task scsi memory allocations to
be private to scsi-lowlevel since is is never accessed from anyehwere else and
it is private to this function.
Remove the pointer to the user data in the list head and replace it with a zero length buffer at the end of the header.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
qemu-kvm calls iscsi_parse_url_full() with iscsi = NULL.
In case there is an invalid URL specified qemu-kvm segfaults when
it tries to set iscsi->error_string.
I tried to patch this in qemu-kvm, but the initiator_name is dirived
from the target name so this seemed to be the easier approach.
Quoth gcc-4.6.3:
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I. -I./include "-D_U_=__attribute__((unused))" -Wall -W -Wshadow -Wstrict-prototypes -Wpointer-arith -Wcast-align -Wwrite-strings -g -O2 -MT lib/socket.lo -MD -MP -MF lib/.deps/socket.Tpo -c lib/socket.c -fPIC -DPIC -o lib/.libs/socket.o
lib/socket.c:445:1: warning: 'inline' is not at beginning of declaration [-Wold-style-declaration]
Fix this and make it a static function.
Also remove trailing whitespace from this file while at it.
Signed-off-by: Arne Redlich <arne.redlich@googlemail.com>
gcc-4.6.3 reports these:
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I. -I./include "-D_U_=__attribute__((unused))" -Wall -W -Wshadow -Wstrict-prototypes -Wpointer-arith -Wcast-align -Wwrite-strings -g -O2 -MT lib/init.lo -MD -MP -MF lib/.deps/init.Tpo -c lib/init.c -fPIC -DPIC -o lib/.libs/init.o
lib/init.c: In function 'iscsi_parse_url':
lib/init.c:410:18: warning: 'l' may be used uninitialized in this function [-Wuninitialized]
lib/init.c:409:10: warning: 'target' may be used uninitialized in this function [-Wuninitialized]
Both warnings appear to be spurious though, as both "target" and "l" are only used if
"full" is set, which implies that these are initialized before.
Signed-off-by: Arne Redlich <arne.redlich@googlemail.com>
Send a large number of DATA-OUT PDUs that do not have a matching SCSI-COMMAND
PDU and verify that the target responds correctly. Either by terminating the
session or by just ignoring the data.
Verify also that the target is not "surprised" and crashes.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
qemu-kvm/qemu-img starts in+out polls from the socket before the connection is
established. This leads to a hang if the connection cant be established
(i.e. the target is down when qemu-kvm is started).
before:
LIBISCSI_DEBUG=2 qemu-img convert -f iscsi -O raw iscsi://127.0.0.1/iqn.2004-04.com.qnap:ts-809u:iscsi.lieven20.c53dac/0 /dev/null
libiscsi: connecting to portal 127.0.0.1 [iqn.2004-04.com.qnap:ts-809u:iscsi.lieven20.c53dac]
libiscsi: read from socket failed, errno:111 [iqn.2004-04.com.qnap:ts-809u:iscsi.lieven20.c53dac]
libiscsi: connection to 127.0.0.1 established [iqn.2004-04.com.qnap:ts-809u:iscsi.lieven20.c53dac]
->success!!
after:
LIBISCSI_DEBUG=1 qemu-img convert -f iscsi -O raw iscsi://127.0.0.1/iqn.2004-04.com.qnap:ts-809u:iscsi.lieven20.c53dac/0 /dev/null
libiscsi: iscsi_service: socket error Connection refused(111) while connecting. [iqn.2004-04.com.qnap:ts-809u:iscsi.lieven20.c53dac]
libiscsi: Failed to connect to iSCSI socket. iscsi_service: socket error Connection refused(111) while connecting. [iqn.2004-04.com.qnap:ts-809u:iscsi.lieven20.c53dac]
qemu-img: iSCSI: Failed to connect to LUN : Failed to connect to iSCSI socket. iscsi_service: socket error Connection refused(111) while connecting.
qemu-img: Could not open 'iscsi://127.0.0.1/iqn.2004-04.com.qnap:ts-809u:iscsi.lieven20.c53dac/0': Invalid argument
qemu-img: Could not open 'iscsi://127.0.0.1/iqn.2004-04.com.qnap:ts-809u:iscsi.lieven20.c53dac/0'
Dont requeue data-out pdus, or other pdus with the DELETE_WHEN_SENT flag, such
as nops.
These, like the DATA-OUT pdu will instead be automatically re-sent when the original write command is sent again.
Signed-off-by: Ronnie Sahlberg <ronniesahlberg@gmail.com>
This patch adds support for setting TCP_SYNCNT to overwrite
the system default values. This allows indirect support
for a configurable connect timeout.
Linux uses a exponential backoff for SYN retries starting
with 1 second.
This means for a value n for TCP_SYNCNT, the connect will
effectively timeout after 2^(n+1)-1 seconds.
This patch allows the following parameters inside libiscsi to be adjusted without code modification:
LIBISCSI_DEBUG
LIBISCSI_TCP_USER_TIMEOUT
LIBISCSI_TCP_KEEPIDLE
LIBISCSI_TCP_KEEPCNT
LIBISCSI_TCP_KEEPINTVL
You can now enable debugging of libiscsi inside e.g. qemu-kvm with
LIBISCSI_DEBUG=3 qemu-kvm -hda iscsi://...
This patch adds 3 functions to set the 3 keepalive values TCP_KEEPIDLE, TCP_KEEPCNT
and TCP_KEEPINTVL. The values have to be set after iscsi context creation and are
then configured on the socket on each new connection.
For TCP_USER_TIMEOUT to work it seems to be necessary that SO_KEEPALIVE is
enabled. RFC5482 section 4.2 also says that the TCP_USER_TIMEOUT has to be
less than the keepalive timeout. This means less than 30000 ms in the
current libiscsi default settings for TCP keepalives.
This patch adds a linear backoff mechanishm + jitter in case
a reconnect fails. If there is a longer outage this is to
avoid a large amount of simultaneous connects to the storage.
This patch adds a user configurable option to set the TCP_USER_TIMEOUT
socket option. With this timeout set a broken TCP session is shutdown
after a given timeout even there are unacked packets. SO_KEEPALIVE
seems not to work in this case.
RFC3270 describes in section 12.14 that immediate and unsolicited data
sent from the initiator to the target must not exceed FristBurstLength
bytes in total.
